Send message when a timeslot opens up.

What does this mr do?

Send a user updates on requests which have become available because of slots opening on the server side.

Screenshots

before

after

Does this MR meet the acceptance criteria?

• I have added a changelog entry to reflect the significant changes I made.
• Tests were created to test the feature.
• I have updated the documentation accordingly.
• I adhere to the style guide.

Closes #659 (closed) #569 (closed)

src/main/java/nl/tudelft/queue/cache/AssignmentCacheManager.java

@@ -22,14 +22,14 @@ import java.util.stream.Collectors;
 
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Component;
-import org.springframework.web.context.annotation.RequestScope;
 
 import nl.tudelft.labracore.api.AssignmentControllerApi;
 import nl.tudelft.labracore.api.dto.AssignmentDetailsDTO;
 import nl.tudelft.librador.cache.CoreCacheManager;
+import nl.tudelft.queue.scope.CacheScope;
 
 @Component
-@RequestScope
+@CacheScope
 public class AssignmentCacheManager extends CoreCacheManager<Long, AssignmentDetailsDTO> {
 	@Autowired
 	private AssignmentControllerApi api;